We describe and evaluate a new method for determining isolipases inserum.Two forms of lipase, L1 and L2, were identified by this method. Adifferent surface charge is the basis by which both isolipases are separatedby electrophoresis in a buffered agarose gel. After electrophoresis, thebands in the gel are detected by the following specific colorimetric chemicalreaction sequence.

A violet complex is formed at the site of each fraction; this patternmay be visually interpreted or quantitated by scanning with a densitometerat 550 nm. All studied samples showed two bands of lipase activity. Themost anodal fraction to the application point is L1 and the most cathodalfraction is L2, numbered in conformance to the convention of the InternationalUnion of Biochemistry.

a- 10 is the maximun number ofsamples suitable of be appliying on the same agarose gel.

b- 6 is the maximun number of gels that can be processedwith the same substrate vial.

Fig. 5:Precision of the isolipases fractionationby Electrophoresis.

REFERENCE INTERVAL FOR ISOLIPASES: Reference values were establishedby calculating the mean values ± 2 DS, from a population of healthymale and female adults.L1( 0 to 16%) and L2 (100 to 84%) of total lipase activity(77 ± 43 U/L). We calculated L1/L2 ratio, with a reference valueof L1/L2 = or <0,25.

CLINICAL STUDIES: L1 and L2 percentages and L1/L2 ratio were calculatedand compared with the control group.